Fuse for shells.



H. PRAHL.

FUSE FOR SHELLS.

APPLICATION mzo JULY 25,1913.

Patented Feb. 6, 1917 2 SHEETS-SHEET I.

. m nw U 4/ L, y \\\A,

H. PRAHL.

FUSE FOR SHELLS.

APPLICATION FILED JULY 25, 1913- 13143 586. Patented Feb. 6,1917.

2 SHEETS-SHEET 2- LJ U N n- E 5E5 15 HUGO ?BAIEL, OE IDUSSELDGRF, GERMANY, ASSIGNOR T0 RHEINISCHE METALL- WAAEEN- UHD BEASCZ-IINEHFABRIK, 0F

FUSE FOE DUSSELD ORF- DERENDORF, GERMANY.

SHELLS.

Specification oi Letters Patent.

Application filed July as, 1913. Serial No. 781,171.

To all wliom it may concern:

Be 'it known that I, Hose PnAnL, engineer, a subject of the German Emperor, and residing at 14 Moltlzestrasse, Dusseldorf, Germany, have invented certain new and useful Improvements in Fuses for Shells; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the 8.111 to which it appertains to make and use the same.

This invention relates to fuses for shells of the type which are set by timing caps and wherein automatically operating means, such as clock mechanism, may be used to control firing.

The object of my present invention is to provide means whereby a single firing pin -may be controlled by percussion or time mechanism; and a further object is to avoid having any mechanical connection between the firing pin releasing mechanismand the timing cap.

In the accompanying drawings, Figure 1 is a. vertical longitudinal sectional View showing the parts in the position they assume before firing. Fig. 2 is a side elevation of the releasing mechanism, taken at right angles to the position shown in Fig. 1. Fig. 3 is a plan view of Fig. 2, showing the releasing mechanism in its locked position.

Fig. 4 is also a plan View showing the releasing mechanism unloclzed. Fig. 5 is a side elevation with the parts in the position indicated in Fig. at. Fig. 6 is plan View showing the means engaging and holding the firing pin. Fig. 7 shows the position of the releasing parts and firing pin before fir- Fig. 8 shows the same parts after firing and before ignition. Figs. 9 and 10 are, respectively, plan views of the parts shown in Figs. 7 and 8. Fig. 11 shows the same parts after being released by clock mechanism. Fig. 12 shows the sameparts when released by impact. Figs. 13 and 14 are plan views of the parts shown in Figs. 11 and 12, respectively.

Referring to the drawings, 3 designates the firing pin; 4%. the main-spring therefor, and 28 the priming cap which is designed to be exploded by the pin on the recoil of its spring. The pin is normally held retracted by a spiral flange of a rotatable member 28 engaging the underside of the fianged heed of thefiring pin. The pitch or inclination of the flange 7" is such that the tension of spring 4:, acting through the firing pin, constantly tends to rotate member 23 in the direction to efi'ect the release of the firing pin.

The rotatable member 23 is provided with two laterally projecting shoulders c and 9 located in different planes and with which a'pin 25 of a longitudinally-movable trip bolt 15 is designed to engage. This bolt 15 parallels the firing pin and the rotatable member 23, and is slidably mounted in an outer plate L and an inner plate L. At the first impulse, on firing, the bolt 15 slides inwardly or rearwardly, owing to its inertia,

causing the pin 25 thereof to disengage shoulder e and allow the releasing member 23 to be partially rotated under the influence of spring 4:, aided or not by centrifugal force. The rotation of the member 23 is arrested when the more inwardly located shoulder g strikes against the end of pin 25, as shown in Figs. 8 and 10. The arrangement of shoulder g relatively to pin 25 is such that as soon as boltElS is moved, either on its axis or longituinallythereof, the member 23 will be rotated sufficiently, under the recoil of spring 4, to allow the firing pin to free the fiange f and be impelled by said spring.

When the device is used as a percussion fuse the release of member 23,-that is, the disengagement of pin 25 from shoulder g, (see Fig. 12)occurs when bolt-l5 moves forward on impact. When, however, time mechanism is employed, at a predetermined point bolt 15 will be permitted to rotate on its axis under the pressure of the mainspring, and such rotation being unimpeded the firing pin will be projected forward as soon as it clears flange f. V

Itshould be pointed out that the two shoulders e and g are fixed at certain angles to the longitudinal axis of the releasing bolt '15 in order that a certain resistance shall be interposed to prevent such bolt, or its pin 25, from sliding inwardly on shoulder e or outwardly on shoulder 9 under the action of the main-spring, but this resistance must be overcome when the gun-is fired or at the impact of the shell.

The trip or releasing bolt 15 carries at its outer end a pin '2' which projects through the outer supporting plate L and is equipped ,with a laterally extending finger 13 with Patented see. c, rear.

' 25' 13 of the releasing bolt.

setting cap 38 holds the catch in its locking which releasing mechanism isdesigned to engage so as to normally prevent the axial rotation of the bolt, and particularly when the pin 25 thereofis in engagement with 5 shoulder 9 after firing but before the predetermined point has been reached for the eX- plosion. The releasing member with which the fi ger 13 engages is shown in the form of a [ring 21 which is formed ,wi'th an opening 19 to accommdoate the projection c .(Fig. 5) 0 a locking arm 22 which is rigidly connected to a centrally arranged. shaft 29 which is designed to be rotated by automatically operating means, such as clock-mechanism, not shown. The ring 21 is designed to be'locked to. arm 22 by means of a catch 7 '20 pivoted to said arm at (Z and havinga pin or projection Z which is designed to en- 7 ter coincident openings in the ring and arm, as shown in Fig. 3. The catch is normally under the tension of a spring 6 which tends to unlock the catch and release the locking ring 21 so that'it may be moved laterally under the pressure exerted thereon by finger The inner wall of position.

Before the initial impulse, the releasing mechanism is held by pin iof bolt15, such 30 pin lying in the path of arm 22 to prevent the counter-clockwise rotation thereof as shown in' Fig. 3. When the arm 22 is so held by pin 71 the catch 20 holds ring- 21 to arm 22. This is the normal position of the releasing device before firing.

ever the releasing bolt 15 moves inwardly or rearwardly, at the first impulse, the pin 2' is Withdrawn'from the path of arm 22, and the latter, together .with the releasing ring 21, is 40 permitted to rotate under the action of the clock-mechanism, and pin 25 is disengaged from shoulder e. The bolt 15, after the firing, is prevented from rotating on its axis so long as ring 21 remains locked to arm 22, 46 but when said ring is released bycatch 20 it y will permit thebolt to rotate under the recoil of spring 4, pin 25 being moved out of the way by shoulder 9. While the clockwork is rotating arm 22 counter-clockwise, 50 the catch 20 remains in locking position until it arrives opposite a recess m formed in the interior of the timing cap 38, whereupon said catch being projected into said recess by the action of its spring I), the locking ring 21 will .be released, and under thejpressure of finger 13 will be moved laterally, permitting the release of the firing pin.- The setting is effected by adjusting the'tim- -ing cap 38 which alters the position of recess m, and according to the position of such recess the ignition is accelerated orretarded. The percussioh ignition is always ready for action and requires no special setting.

In order that the clockwork or the time I 6 ignition should not explode the shell before misses impact, apin 17 secured to plate L allows the arm 22 and the catch 20 to rotate with thfi shaft 29 only t rough a given angleofabout 320 or t} of circle. The catch 20, which is turned by the clockwork through the shaft 29 and arm 22, can only describe an are 01* about 320. If cap'38 is set so that the rece'ss m lies in the remaining are of 40, the

catch 20 cannot enter the recess m during: the 1 time the clockwork is in action and hence ignition is impossible under such setting. In that event, the release of the member 23 and the firingpin 3 can only occurwhen'the releasing bolt 15 has been caused. to slide forward on theimpact of the shell (see Fig. 12).

The pin 17 in the normal position of the releasing parts before the gun is fired is di rectly behind the catch 20 or the arm 22, (Fig.3) so that it takes up any harmful re action of the parts 22 and 20 on the shaft 29 and the clockwork when the shell begins to, rotate. The parts 22 and 20 would otherwise by reason of their inertia turn. the shaft 29 in the opposite direction to that intended,

that is, in a clockwise direction. Gtherwise' a small pinion (not shown) on the shaft engaging wlth the wheel work of the clock would be. bent or broken. 7 The pin 17 there fore serves a double purpose.

According to my present invention the recoil of the mam-spring is utilized to free the firing pin from the restraining mecha;

nism; and the same parts may be employed for either time or impact ignition.

I claimas my invention:

1. A shell fuse comprising a. spring-impelled firing-pin, means for normally holding said firing pin retracted and capable of being moved to release said'pin by the recoil of the spring thereof, a trip for said holding means comprising a rotatablyqnow able member, and time mechanism for permitting the rotation of said trip member under the recoil of said spring.

'2. A shell fuse comprising a spring-impelled firing-pin, means for normally hold-- ing said firing-pin retracted and capable of being moved to releasesaid pin by the recoil' ill-5 of the spring thereon, a trip for said hold-- the rotation of said trip-member under the recoil of said spring, said rotatably movable member preventing action of said timeholding means comprising a longitudinally and rotatably-movable bolt, and time-mechanism for permitting the rotation of said belt, which latter norma y prevents action.

lng means comprising a. rotatablymovable. member, and time-mechanism for permitting "of said time-mechanism but is automatically fmoved out of the Way upon firing. 4. The combination with a spring-impelled firing-pin, of a holding member therefor designed to be moved into releasing position by the tension of the firing-pin spring, said holding member having two shoulders on different planes, a longitudinally-movable trip-bolt having a projection for sucm ces'sively engaging said shoulders, said'bolt being moved longitudinally on firing to disengage its pin from oneshonlder and permit it to be engaged by the other shoulder, and timing-mechanism for permitting said 735 bolt to rotate to disengage its pin from said second shoulder at a predetermined point after firing. 5. The combination with a spring-impolled firingpin, of a rotatable holding 20 member therefor having a spiral flange with which the head. of the firing pin engages, said member also having shoulders, a bolt having a pin for successively engaging said shoulders, and means for permitting said bolt to release saidholding member. 7 6. The combination with a firing pin, and means for normally holding the latter r tracted, of a time-controlled arm, and a longitudinally-movable member normally arresting said arm and holdin means designed to be moved automatieall 50 release said arm and at a predetermine point after firing to release said holding ans.

7. The combination with a 'ring pin, and means for normally holding the latter retracted, of a time-controlled arm, a releas- ,seo

7 after firing to release said holding means.

s aid holding means and having a finger L unlocks said releasing member permits sa ing member normally locked to said a and a longitudinally-movable and rotat member normally arresting arm holding means and designed on h 'ing lease said arm and a predetermined. no

8. The combination with firing pin, and means for normally holding the latter re traeted, of a time-controlled arm, a releasing member normally locked to said arm, a catch for efiecting such looking, a beltfor normally arresting said and holding means, and means for releasing 6f 1 'Whereby said bolt may lie turned to tree said holding member.

9. A shell fuse comprising a casing, a having a recess, a firing-pin, for, mally holding the latter retracted controlled ar ng a releasing member, a catch for normally locking. said releasing member to said arm, a longitudinally movable and rotatable bolt initially in the path of said arm and designed to be moved from such path on firing, said bolt nor ally hold g L engaging said releam'ng member which latter when said catch .enters said recess bolt to rotate to free said holding means. I

In testimony whereof, I. have signed this specification in the presence of two snbscribing witnesses.

HUGO PRAHL. [n Witnesses:

HELEN Norma, ALBERT 'llKIFER. 

